This invention relates to an apparatus and method for aligning a data card for transfer of data to and from the card. More specifically, the data card has an annular data storage region on one side and data is transferred to and from the annular data storage region by rotating the card relative to a non-rotating data transfer assembly.
Wallet-sized cards are in widespread and general use as credit cards, identification cards, passes, membership cards, driver's licenses and the like. Such cards are typically made of a solid plastic or a plastic laminate and carry visible indicia, plus embossed or raised characters which carry the person's identification, the card's identification and/or other information. Such cards are used for imprinting sales receipts, and most of such cards carry magnetic strips which contain limited amounts of digitally-encoded data. Information is transferred to and from the magnetic strips of these cards by a linear card-reading arrangement. For example, a card is inserted linearly into a card reader (such as an automatic teller machine), or one edge of a card bearing a magnetic strip is passed linearly across a reader (such as a credit card reader).
The use of higher data density optical recording techniques has been extensively explored in recent years. In optical data transfer systems, a focused laser beam is used to illuminate and detect the data encoded on the media. In a magneto-optic format, it is possible to read, erase and write data on the media with a focused laser beam in combination with a magnetic bias field adjacent the illuminated media. One form of optical recording is a disk format and is exemplified by the now-familiar "compact disk" or "CD" format for audio recordings. Optical data storage arrangements have been suggested for wallet-sized cards, with the information aligned in a linear or strip storage format, as discussed in Maurer et al. U.S. Pat. No. 4,467,209 and Drexler U.S. Pat. No. 4,544,835.
It has also been suggested that data be recorded on a card in a non-linear fashion. Lemelson et al U.S. Pat. No. 4,592,042 discloses a card reader for use in transferring data to and from a card which has data encoded thereon in an arced format. Vogelgesang et al. U.S. Pat. No. 4,812,633 and Slafer et al. U.S. Pat. No. 4,831,244 disclose cards which include a data region having data tracks aligned concentrically or in a spiral format so that the information can be read or placed on the data region of the card while the card is rotated.
The use of a card having an annular data storage region presents unique problems in terms of data transfer. In order to effectuate high rate data transfer, the card must be rapidly spun relative to a non-rotating data transfer assembly which then follows the either concentric or spiral tracks of data on the card. In order to effectively transfer data to and from such a card, an effective arrangement for card handling and presentation to the data transfer assembly is required. In handling such cards it is critical that the sensitive area on the card for data storage be protected from rough handling. For of an optical data card, the area must also be optically visible. Furthermore, because of the close spacing of the data tracks on such cards, extremely high accuracy in card alignment relative to the data transfer assembly is required. In addition, such high accuracy is required in all three axes (x-y-z) of the card during data transfer. It is further desirable to rotate the card very rapidly in order to achieve a high rate of data transfer. Finally, a system is needed that is easy to use (such as an automatic teller machine) for a person presenting a card for data transfer.